All In
by puuurpleprincess95
Summary: Choices are made. There's no turning back after you make them, or is there? What happens when Lexie discovers that she is pregnant with either Mark or ALex's baby months after breaking up with Mark.
1. Chapter 1

Just a little idea that I had. I really like this idea and have already written the entire thing in my head, but life is crazy, so you might not get an update for a while. But I have a four day Easter weekend, so there is some hope.

The title is one of Lifehouse's new songs.

Takes place mid-May. Will be an actual date in the next chapter.

I don't own anything.

* * *

"Lexie!" Meredith called as she ran up the stairs annoyed. Lexie had the day off and Meredith had just gotten home. She had been calling for Lexie for the past little bit and she had not been answering.

She opened the door of Lexie's room and saw her sister sitting in bed in with her hair in a sloppy ponytail, wearing her favorite pair of Under Armor shorts, and a grey Columbia T-shirt that she already knew was Mark's. She knew something was wrong. Lexie's face was red and she was sweaty. Looking down she realized that Lexie was wearing her sneakers. She had been running. They didn't run.

"Hey, what's going on?" Meredith said sitting on the bed across the bed from Lexie.

Lexie didn't say anything. She simply opened the bedside drawer and took out a pregnancy test.

"Oh, Lexie." Meredith said looking at it. It was positive. "Are you sure?" She said looking at her little sister.

Lexie nodded and pulled out a plastic baggy. There were eight more tests and they were all positive.

Meredith looked at her little sister. The whole time she had known Lexie she had never seemed as scared as she did now. She looked small and afraid. It made Meredith realize how young Lexie truly was.

"It, it could be Mark's." Lexie stuttered out.

"Lexie, you'd have to be what… 5 months pregnant? You're a doctor, you would have noticed."

"I haven't exactly been thinking about that kind of stuff." Lexie said sharply. "And look." She said pulling her shirt up.

Meredith gasped. There was a small, but defined baby bump.

"Lexie, how could you not know?" Meredith asked her sister in astonishment.

"Well, I haven't really been paying attention to eat and I've already eaten my way up a scrub size because of everything that's happened. And I've only thrown up maybe once or twice, but it was when I was around Mark so I figured it was just nerves."

"Well, didn't Alex notice?" Meredith asked.

"Mer, I stopped sleeping with Alex a month ago."

"Oh." Meredith said.

"What am I gonna do?" Lexie groaned leaning against the bed frame and slowly rubbing her fingers over her stomach.

"Well," Meredith said sitting beside Lexie and letting her sister lean her head on her shoulder. "You're gonna get some sleep and tomorrow I'm going to think of a plan in the morning."

"Meredith." Lexie said quietly.

"Yeah, Lex?"

"This baby has to be Mark's."

"I know Lexie, I know." Meredith said before they both drifted off to sleep.

"Hope is like a bird that senses the dawn and carefully starts to sing while it is still dark."


	2. Chapter 2

I don't own anything. Hope you like it. Review!

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"Okay, so this is going to be a little cold." Meredith said, taking out a tube of ultrasound gel.

"I know, I know. Just hurry up before someone discovers that we're in here." Lexie said anxiously. They had snuck into an examination room where the ultrasound machine was stored. They were supposed to be doing rounds.

"Relax. Derek is covering for us." Meredith said calmly as she turned the machine on. They had told Derek last night.

"Yeah, but he's not the chief anymore." Lexie snapped. She was right. About a month ago Derek had had a meeting with the board and they had all decided that it was time for Richard to become chief again. Derek was happy because he got to be a surgeon again.

"No, he's not." Meredith said as she started to run the ultrasound wand over Lexie's tummy.

Lexie was about to retort, but was silenced as a picture filled the screen.

Despite all of the drama she would probably later have to endure, Lexie smiled. That was her baby. She hoped it was her and Mark's, but even if it wasn't it was hers.

She looked up and saw Meredith grinning at her.

For a minute the sisters stared at the screen in awe, but then Lexie asked the question that had been on her mind.

"How many weeks?" She asked Meredith nervously.

"17." Meredith replied.

"So let's see," Lexie said thinking. "It's May 13, so conception is…. Around January 14. Damn it!"

"What's wrong?"

"It could be either of them. That's the last few times I slept with Mark and the first few times I slept with Alex."

"Oh." Meredith said. "So, do you wanna find out the sex?" She asked, amazed that her sister was already that far along.

"Yeah, that's one less thing I have to wonder about." Lexie replied.

"Okay…. I get a niece!" Meredith exclaimed excitedly.

"Mer, you already have a niece…" Lexie said laughing.

"But this is different!" Meredith said as she handed Lexie a paper towel.

"Okay!" Lexie said laughing. "Can I have two copies of the picture?" Lexie asked as she wiped the gel off of her stomach.

"Better make that three!" Meredith said laughing as she printed one for herself.

Lexie grabbed the photos and looked at Meredith sternly. "Don't tell anyone, even Cristina. I don't care if Alex finds out from someone else, but I'm going to tell Mark."

"Okay." Meredith said, but right before Lexie opened the door she said, "Oh, and Lexie."

"Yeah?" Lexie asked.

"Good luck."

"I'll need it." Lexie muttered as she closed the door behind her.

Lexie walked down the hall. For some reason, now that she knew she was pregnant she felt like everyone was watching her even though they weren't.

She saw Alex coming out of an on call room with a nurse and she quickly scribbled out a note and thrust it in his hand.

He leaned against the wall and read it.

It said: Alex, I'm pregnant. She may or may not be yours. I'm not expecting anything. If she is yours than I will let you know. Lexie.

He looked up at her and nodded and then walked away.

Lexie spent the day on Mark's service. She didn't want to tell him just yet because they were working on a little girl in peeds and she knew that if she told him, he wouldn't concentrate and might damage the poor little girl's hearing for the rest of her life, but watching how good he was with her gave Lexie some hope that maybe everything would be alright. She had no idea what she was going to do if the child inside of her was Alex's.

…….

Later that night after surgery, after Mark had saved that little girl's hearing, after Lexie found out that he had broken up with Teddy earlier that morning, and after for the first time since they had broken up he had let Lexie do part of the procedure and his hand gently grazed hers, Lexie stopped him on their way out of the scrub room.

"Could we talk?" She asked gesturing towards the open on call room.

"Lexie, I…"

"Please. It's important." She said. Mark looked down at Lexie. Her dark brown eyes were begging him to come and he could see the brown hair staring to grow back. He had heard from Derek that she wasn't going to dye it back and it had made his heart soar.

"Okay." He said as they walked into the on call room.

"She might be yours." Lexie said taking the picture out of her pocket and putting it into his hand.

Mark could feel the room start to spin around him as he looked at the picture. The words were ringing in his head. _She might be yours._

"I can understand if you're mad and don't walk to talk to me and if you don't want her. Because this is my fault because I broke up with you and let you leave and now-" She started to ramble before Mark cut her off by kissing her.

"Now, I came back and am never leaving again." Mark said smiling as they pulled apart. "I'm sorry about everything. About everything with Sloan, and being hypocritical and immature, and sleeping around, and for making your think I was moving on."

"Dido." Lexie said laughing.

"Lexie, I love you." He said cupping her face in his hands. "And I don't care whose little girl this turns out to be because she is going to be my daughter, biological or not."

Lexie had started to cry. Just like she had over the past few months. But this time she wasn't crying alone or Meredith was trying to comfort her. This time Mark held her tightly in his arms and gently spoke to her.

"I'm scared." She whispered as he held her against his chest.

"You don't need to be." Mark said gently stroking her stomach with the tips of his fingers.

"I'm scared." She repeated. "I'm scared that she won't be yours."

"Lexie," he said laughing, "She will be. And she's going to be the biggest spoiled rotten Daddy's Little Girl in the history of mankind. Isn't that right, baby girl?" He said in a silly voice as he placed butterfly kisses on Lexie's belly.

"Mark!" Lexie gasped.

"What?" He asked anxiously.

"She moved. The baby moved!"

"See, she knows who her Daddy is!" Mark said excitedly.

He kissed her and then got up and started to pull Lexie up.

She refused to budge. "Mark, I'm pregnant. Let me sleep."

"Yes, you're pregnant and that's exactly why you are coming home to sleep instead of in an on call room where you'll just be woken up by people having sex."

"Good point." She said as she quickly sat up.

"Let's go home." He said grabbing her hand.

She followed him out. They quickly went to Meredith's house to get Lexie's stuff and then went home.

Lexie fell asleep after about an hour of talking, but Mark lay awake. He held his future in his arms. Lexie and his daughter. He knew that there was a possibility that the baby would be Alex's, but he had a good feeling about this. He fell asleep with his girls in his arms.

"If you love somebody, let them go, for if they return, they were always yours. And if they don't, they never were."


End file.
